1. Field of the Invention:
The present invention is generally related to portable cellular telephone systems and, in particular, to a case system, conformant to a compact and complexly shaped portable cellular telephone system, that includes a microprocessor system providing supplementary control and signal processing functions.
2. Description of the Related Art
There exists a class of cellular telephones known as compact portable cellular phones. This class is generally characterized by a collapsible or foldable case structure that permits carrying of the cellular phone in a shirt or coat pocket or small purse. A particular attractiveness of such phones is specifically the small size of the phone.
One such exemplary compact portable cellular phone is the Motorola Micro-TAC series of phones. The Micro-TAC phones employ a flip down sound deflector structure to expose the numeric key pad and a numeric display. A rechargeable battery is rail mountable to the back surface of the phone. Planar slide contacts that mate on the adjacent surfaces between the battery and cellular phone provide operational power.
While the small size and portability of the Micro-TAC phone are primary advantages, products exist to permit the utilization of the Micro-TAC in more conventional settings. Specifically, a fixed mounting structure is known that permits the Micro-TAC to be temporarily mounted in a fixed position in, for example, an automobile. An access connector receptacle is provided at an external surface of the Micro-TAC separate from the battery attachment surface to permit access to the internal cellular phone electronics. Once the Micro-TAC is placed in the fixed mounting unit, a conventional flexible connector is manually attached to the Micro-TAC phone by way of the connector receptacle. The connector allows for a conventional external antenna, microphone and amplified speaker to be attached to the Micro-TAC. The conventional connector utilized for insertion into the receptacle disables the conduction of power from any attached battery and, further, disables the internal microphone and speaker sub-systems of the Micro-TAC phone. Disconnection of the external connector and removal from the fixed mounting unit re-enables these functions of the Micro-TAC and thereby permits portable use of the Micro-TAC phone.
Another product known to be used with Micro-TAC type cellular phones is mobile battery eliminator and recharging unit. Normally, the rechargeable battery must be recharged in an AC adapter with the battery either separate from or normally mounted to the cellular telephone unit. The battery eliminator connects to the Micro-TAC cellular phone to couple automotive 12 volt DC power to the phone. The battery eliminator may also permit mounting of a rechargeable battery to the eliminator product at the same time permitting the battery to be simultaneously recharged without interruption in the use of the cellular phone.
Electronics adapter units, providing additional electronic functionality, are also known in relationship to mobile and transportable cellular telephones. An exemplary adapter unit is a Hand-held Privacy Unit (HPU-100) that provides proprietary voice encoding for cellular transmissions. The adapter unit attaches to a substantially planar rear surface of the cellular phone. The original manufacturer of the cellular phone provides both large pad power connectors as well as large pad electronics access points for tapping analog voice information from the cellular telephone internal circuitry. The large pad contacts are intended to enable simple contact between the cellular telephone and adapter unit while at the same time presenting only very loose tolerance requirements in the mating of the contacts. Although the rechargeable battery may be further mounted to the attachment unit, a separate microphone and independently powered speaker amplifier system must be provided in order to enable use of the system. Consequently, the resulting system does not provide a single unitary cellular telephone system providing for the provision of additional electronic functions.
Other specialty cellular phones are known to include specialized functions as an integral feature of the cellular phone. For example, a cellular phone is known to incorporate a dedicated and highly-specialized data modem as part of the electronic circuitry of the cellular phone to permit signalling and sign-on communication links with the main cellular switch. Such phones may be connected to, for example, a personal computer to enable cellular digital data communication. However, in such instances, the internal modem is essentially unaccessible and a separate modem is required.